Question

the distance from earth to the moon is approximately 3.84x10^5 km. how long would it take a radio wave with the frequency 7.25x10^5 Hz to travel from Earth to the moon

Answer 1

The time that would take a radio wave with the frequency of 7.25 x 10^5 Hz to travel from earth to the moon is 1.28 sec

Calculation

Time = distance / speed

distance = 3.84 x 10 ^5 km

convert Km to m

1 Km= 1000 m

3.84 x10^5km= ? m

by cross multiplication

= (3.84 x 10^5 km x 1000 m) / 1 km = 3.84 x 10 ^8 m

Speed of light= 3.0 x 10^8 m/s

therefore time = 3.84 x10^8 m / 3.0 x10^8 m/s = 1.28 sec